Helena Alexandersson

Helena Alexanderson

Professor

Helena Alexandersson

Postglacial sedimentary and geomorphological evolution of a small sub-Antarctic fjord landscape, Stromness Bay, South Georgia

Författare

  • Nathalie Van der Putten
  • Cyriel Verbruggen
  • Helena Alexanderson
  • Svante Björck
  • Bart Van de Vijver

Summary, in English

A detailed stratigraphical, palaeoecological and geomorphological reconstruction of a fjord head on South Georgia (Husvik, Stromness Bay) is presented. Six sites were chosen to reconstruct the lithostratigraphy of the area by means of coring. A maximum depth of 11m was attained and the sediments encountered vary from coarse gravel over sands to fine silts with, in some cases, intercalated peat layers. Diatom analysis allowed determination of whether the sedimentological units were deposited in a marine or freshwater environment. Six radiocarbon dates constrain the chronology. Deglaciation of the area was completed in the early Holocene and the postglacial geomorphological evolution of Husdal (unofficial name) was controlled by fluvio-deltaic deposition and sea level changes. Relative sea level rise was faster than, or kept pace with the isostatic rebound of the land. Our results challenge the presence of Late Glacial and Holocene raised beach deposits in the area as reported in earlier geomorphological studies.

Ämne

  • Geology

Nyckelord

  • diatoms
  • Holocene relative sea level
  • raised beaches
  • stratigraphy
  • sub-Antarctic island

Status

Published

ISBN/ISSN/Övrigt

  • ISSN: 1365-2079